The present invention relates to a continuous casting machine such as a mold-type continuous casting machine that is used to continuously produce copper ingots having a diameter of, for example, 200 mm or a belt-wheel type continuous casting machine that continuously produces ingots having a smaller sectional size which are used for producing copper or aluminium rods and, more specifically, to an automatic molten metal surface level control system to maintain the surface of molten metal poured in such casting machines at a constant level with a high accuracy and improved responsiveness for improving the stability of the quality of ingots.